Suspicous diagnosis
Case 282
【Progress】
Gastric endoscopy revealed the existence of anisakis worm (Fig. 4).
【Discussion】
Anisakis is a parasite in sea whose eggs reside in shellfish and whose child lava reside in blue-backed fish or squid as an intermediate host and whose adult imago reside in sea mammals such as whale, dolphin and sea lion as final host (1,2). Human is neither intermediate host nor final host. Then, once anisakis with blue-backed fish are invaded in digestive organ in human, they would die within a few days. Several hours after anisakis is ingested with blue-backed fish or squid, symptoms of abdominal pain, nausea, vomiting emerge as called anisakiasis (1-5). Some anisakis can penetrate mural of stomach and/or small intestine, causing these symptoms called anisakiasis. However, some people do not emerge anisakiasis despite they ate the same blue backed fish which caused anisakiasis in others. At present, anisakiasis occurs not only from the direct invasion to murals of gastric and/or small bowels but also allergy to anisakis via IgE production causing histamine secretion from mast cells and eosinophilic cells. It is thought that some allergy to blue-backed fish comes from allergy to anisakis itself (1). Now there is a kit to check whether antibody against anisakis produces or not. It is borne in mind that it is useful to check allergy to anisakis but there is allergy not via IgE bound to antigen from mast cells but directly histamine release from mast cells like anaphylaxis immediately after being stung by hornet.
Anisakiasis is relatively common in Japan where they love eating raw fish. Anisakis dwell in blue-backed fish but not in white meat fish. When blue-backed fish and squid are cooked after heat of 60 degree or more or coldness of 0 degree for a day, anisakis die inducing no occurrence of anisakiasis (1). According to Japan ministration of Health Labor and Welfare in 2018 to 2021in a row, the disease with highest incidence of food intoxication is anisakiasis, followed by campylobacter and norovirus. The most incidence of anaphylaxis is food, drug and anisakiasis.
The bacterial gastric enteritis occurs most in campylobacter followed by salmonella and E coli and the virus enteritis occurs most in rotavirus followed by norovirus (5,6).
【Summary】
We presented a sixty two-year-old male presented in our hospital for gastric pain. Last night, he got mackerel sushi around 7 PM and felt epigastric pain early in the morning. CT depicted a lesion with soft tissue attenuation extending and expanding surrounding gastric mural. Endoscopy revealed anisakis worm at the surface of gastric mucosa. It is borne in mind that anisakis resides in row blue-backed fish and squid they would die in digestive organ in human within 24 hours since human is neither intermediate host nor final host. Anisakiasis occurs not only from the direct invasion to murals of gastric and/or small bowels but also allergy to anisakis via Ig E production causing histamine secretion from mast cells and eosinophilic cells. It is thought that some allergy to blue-backed fish is related with anisakis allergy.
【References】
1.Matsuo S, et al. Small bowel anisakiosis: A report of two cases. World J Gastroenterol. 2006 Jul 7; 12(25): 4106–4108.
2.Shirahama M, et al. Intestinal anisakiasis: US in diagnosis. Radiology. 1992;185:789–793.
3.Takabe K, et al. Anisakidosis: a cause of intestinal obstruction from eating sushi. Am J Gastroenterol. 1998;93:1172–1173.
4.Kim LS, et al. A case of anisakiasis causing intestinal obstruction. Kisaengchunghak Chapchi. 1991;29:93–96.
5.Matsui T, et al. Intestinal anisakiasis: clinical and radiologic features. Radiology. 1985;157:299–302.
6.Guerrant RL, et al. (2001) Infectious Diseases Society of America: Practice guidelines for the management of infectious diarrhea. Clin Infect Dis 32: 331-351.
7.Finkelstone L, et al. Etiology of small bowel thickening on computed tomography. Can. J. Gastroenterol. 2013;26 (12): 897-901
2022.11.11